The Cocktail Party Effect Is Your Natural Party Trick

Ever noticed that when you really want to, you can eavesdrop on a conversation even if it's happening across a noisy crowded room? It's called the cocktail party effect.

Why It's Noteworthy

Humans can single out one person's voice in a crowd—if you think about it, that's pretty impressive. But how do we do it? In a 2012 study, two researchers from the University of California, San Francisco found that while we hear a barrage of noise at once — the roar of a crowd or the mass grumblings in an office meeting — the brain processes and filters that information to focus in on the specific sounds we're interested in. But why do we have this seemingly superhuman power? "The psychological component is that it's a sound we want or need to hear, which is why we can tune into it," co-author Dr. Edward Chan told ABC News. It's why a parent can immediately hear their child when they enter a room of screaming kids, for example.

Why People Are Talking About It

Martin Vestergaard, a neuroscientist at Cambridge University, elaborated on the importance of these findings to New Scientist: "[Because the researchers] looked at brain areas involved in assessing the vocal characteristics of a speaker, rather than just those involved in processing sound, they were able to show that the brain can rapidly enhance a voice with certain characteristics to single it out from others."

Understanding this effect contributes to researchers' understanding of language processing as it relates to disorders like autism, and can also have an impact on artificial intelligence. "Following one speaker in the presence of another can be trivial for a normal human listener," the authors explained in their press release, "but remains a major challenge for state-of-the-art automatic voice recognition algorithms."

While the brain's ability to home in on one thing (even one thing far away) is impressive, it should be noted that it can usually only focus on one thing at a time. So when the person you're talking to at a party seems to be eavesdropping on the couple across the room, he might be... which means he's almost certainly not listening to you. Busted.